Lightning can occur from cloud-to-cloud, within a cloud, cloud-to-ground, or cloud-to-air and occurs in all thunderstorms. Each year lightning strikes the United States 25 million times. Virginia averages 35 to 45 thunderstorm days per year. The rapid heating and cooling of the air near the lightning channel causes a shock wave that results in thunder.
Energy of Lightning
The energy from one lightning flash could light a 100-watt light bulb for more than 3 months. The air near a lightning strike is heated to 50,000°F - hotter than the surface of the sun! Most lightning fatalities and injuries occur when people are caught outdoors in the summer months during the afternoon and evening.
Only about 5% of thunderstorms become severe and can produce tornadoes, large hail, damaging downburst winds, and heavy rains causing flash floods. Heat lightning is a common name for a lightning flash that appears to produce no thunder because it occurs too far away for the thunder to be heard. The sound waves dissipate before they reach the observer.
Watch for signs of changing weather, including darkening skies, sudden wind shift, and a drop in temperature. Have a warning device such as National Oceanic and Atmosphere Administration (NOAA) Weather Radio on hand to get immediate alerts. Staying alert can mean the difference between life and death when a thunderstorm approaches.
Lightning Safety Tips
National Weather Service lightning safety site helps you to learn more about lightning risks and how to protect yourself, your loved ones and your belongings. The site offers a comprehensive page of handouts, links and more.